In both images shown above there is a little white spot in the upper right corner of the red boxes on the right side. For a long time I thought that Henry Holiday and/or Joseph Swain inserted this spot intentionally as a reference to a white spot (used to depict a reflection on the glass) in William Sidney’s painting.
However, there is no white spot in the wood block prints made by Ian Mortimer for a limited edition of The Hunting of the Snark published by Macmillan in 1993. He did not retouch the wood blocks before printing. A detail of that wood block print is shown on the left side of the comparison below. On the right side you see the corresponding detail from the electrotype print used for mass production of the first edition of The Hunting of the Snark in 1876. Therefore I think, that that little white spot just may be a flaw on the metal plate used to print the illustration to The Banker’s Fate.
On the right side of the comparison, the white spot still contains some dark elements. This is true for the first printing. In later reprints of Macmillans 1876 edition, the spot turned completely white and became more and more prominent.
Staff of the Osborne Collection of Early Children’s Books kindly helped me and checked the wood block which is part of their collection. From what they could see, it seems that the woodblock has no flaw at the location where the white spot can be seen in Macmillans 1876 edition of The Hunting of the Snark. I think an analysis which checks whether the wood block had been retouched (bevor it was given to Ian Mortimer for printing in 1993) without damaging the block would be quite difficult.
In my view, there are three possibilities:
- Holiday did not allude to Sidney’s painting. The white spot is an ordinary printing error.
- Holiday alluded to Sidney’s painting. The white spot has been intentionally added on the metal plate.
- Holiday alluded to Sidney’s painting. The white spot is an ordinary printing error which incidentally occurred at the right place. Thanks to Ian Mortimer’s help, by now I think (in contrary to my earlier assumptions) that this is the most probable assumption.